xfs: remove unused XBT_FORCE_SLEEP bit

XBT_FORCE_SLEEP is no longer ever tested; it is only set
and cleared.  Remove it.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
index 5bab046..df7ffb0 100644
--- a/fs/xfs/xfs_buf.h
+++ b/fs/xfs/xfs_buf.h
@@ -90,8 +90,7 @@
 	{ _XBF_DELWRI_Q,	"DELWRI_Q" }
 
 typedef enum {
-	XBT_FORCE_SLEEP = 0,
-	XBT_FORCE_FLUSH = 1,
+	XBT_FORCE_FLUSH = 0,
 } xfs_buftarg_flags_t;
 
 typedef struct xfs_buftarg {